Author(s)
Kaitlyn F. Strickland, MD
Abhishek Gami, BS
Daniel Q. Sun, MD
C. Matthew Stewart, MD, PhD
Affiliation(s)
Johns Hopkins Department of Otolaryngology-Head & Neck Surgery , Johns Hopkins School of Medicine;
Abstract:
Objective: Middle cranial fossa surgery (MCF) is a hearing preservation approach for removal of vestibular schwannomas
(VS). The objective of this meta-analysis is to analyze the rate of successful serviceable hearing preservation (HP) after
MCF.
Data Sources: PubMed, Embase, Scopus, Web of Science, and Cochrane databases were queried in October 2019 for studies
in English reporting outcomes or hearing results after middle fossa approach for vestibular schwannoma.
Study selection: Studies were eligible for inclusion if stratified pre- and postoperative hearing levels were available for ?10
patients. Non-overlapping cohorts were selected for institutions with multiple publications.
Data Extraction: Case volume and years, patient population characteristics, tumor size (intracanalicular or ?1 cm vs. >1cm),
reported HP rate, and hearing classes were recorded.
Data Synthesis: 35 eligible studies representing 2,960 operated ears were identified from 1,075 publications. Serviceable
HP rates were calculated as maintenance of preoperative hearing ?50db PTA and ?50% WRS (AAO-HNS Class A-B,
Gardner-Robertson Class I-II) as well as by ?50% WRS (WRS Class I-II). Pooled effect size for HP rate was computed via
random effects models for the overall cohort and by tumor size.
Conclusions: Overall hearing preservation was 60% (CI 0.56-0.64) for AAO-HNS Class A-B and 71% (CI 0.65-0.76) for
?50% WRS. For intracanalicular / small tumors, HP was 64% (CI 0.56-0.71) vs. 52% (CI 0.43-0.61) for tumors >1cm.
There was significant cross-study heterogeneity (I2=76.76%, ????2=0.05, p=0.00, ?2=146.31, p=0.00) but no significant
publication bias. The MCF offers high rates of successful hearing preservation for removal of vestibular schwannomas,
although a tumor size effect may be present.
Define Professional Practice Gap & Educational Need: Vestibular schwannomas are benign tumors but may cause
significant impairment in patients' quality of life due to hearing and balance dysfunction. An increased emphasis has been
placed on resection via hearing preservation techniques, such as the middle cranial fossa approach; however, the overall
rate of hearing preservation for this approach has not been systematically analyzed across a large cohort of patients. This
meta-analysis investigates the rate of serviceable hearing preservation after middle fossa surgery across the English
literature.
Learning Objective: The middle cranial fossa approach for resection of vestibular schwannomas offers a 60% overall rate
of hearing preservation (and as high as 71% for patients willing to wear amplification devices) for patients with serviceable
hearing preoperatively.
Desired Result: Attendees will improve their ability to effectively counsel patients on the likelihood of serviceable hearing
preservation associated with the middle fossa approach given preoperative hearing levels and tumor size characteristics.
Level of Evidence - III: Systematic review and meta-analysis of cohort studies
Indicate IRB or IACUC: Exempt.